I would seriously advise anyone NOT to get in the habit of deactivating their smoke alarm, whether by using dust covers or removing the
battery etc. The dust covers are only meant to be used during building or decorating work, when high levels of dust are likely. Despite good intentions, it is very easy to forget to re-activate the alarm afterwards, and many fires have been allowed to develop without warning because of this.
If you are getting too many "nuisance" or false alarms, you could try to re-position the detector, especially if it's too close to the cooker/hob.
Or you can replace the smoke alarm with one that has a "hush" button. If it activates whilst cooking etc., you press this hush button and the alarm will be silenced for around ten minutes, without you having to remember to reset it afterwards.
Or you could do as Sparrks says, and fit an "optical" type smoke alarm.
(There are two main types of smoke alarm, the most common being the "ionisation" type which will detect most fires more quickly, and the "optical" type which are not so sensitive, as they react to larger smoke particles. Optical type smoke alarms are more suited to kitchen areas as they are less likely to react to normal cooking fumes.)
Heres an example of a smoke alarm with "hush" button....
Amazon.co.uk: Kidde KID0910UKB Smoke Alarm
And here's an example of an "optical" type....
10 Year Longlife Battery Optical Smoke Alarm - Kidde 10Y29: Amazon.co.uk: DIY & Tools
Whichever type you fit, it should always be fixed to the highest point of the room (ceiling) as this is where smoke will first collect. If you fit it lower down, it may not activate until the higher level has filled with smoke, so your reaction and escape time will be greatly reduced.